A vortex around the z axis can be detected in the x and y component of the velocity field.
Based on the paper
Combining PIV, POD and vortex identification algorithms for the study of unsteady turbulent swirling flows
Laurent Graftieaux, Marc Michard and Nathalie Grosjean
Ecole Centrale de Lyon
Returns the location (x,y), area and circulation of every vortex found.
This is just beautiful. I ended up improving your code to dramatically reduce processing time, as I had thousands of vortex images to track in time. If anyone is interested:
This is just beautiful.
Do you have any tutorial to work with this program? I appreciate you if you can prepare a tutorial on youtube or anywhere.
Quick mode added, bug fixes
Small improvements made.
Added calculation of circulation.